Alright kiddo, so, E85 is a kind of fuel that is used in some cars and trucks in the United States. It is made mostly from corn, which is a kind of plant that we eat or use to make food.
The "E" in E85 stands for "ethanol," which is a fancy word for alcohol that is made from the corn. The number "85" means that the fuel is made up of about 85% ethanol and 15% gasoline.
Now, some cars and trucks can use E85 fuel instead of regular gasoline. This is called a "flex-fuel" vehicle. The reason some people use E85 is that it can be better for the environment, because the corn used to make it is a renewable resource, which means we can grow more of it.
However, not all gas stations have E85 available, so it can be harder to find. And, not all cars can use it - only flex-fuel vehicles. So, if you see a car or truck that says it can use E85, that means it can run on this special kind of fuel that is made from corn.